Patent Number: 6,167,021

Title: Optical recording medium

Abstract: An optical recording medium of the present invention includes a light-transmitting substrate having spiral or concentric grooves formed in at least one major surface, a phase change recording film which is formed on the grooved surface of the substrate and reversibly changes phase upon irradiation of a light beam and thereby changes optical characteristics, and a reflecting layer formed on the phase change recording film, characterized in that the spiral or concentric grooves form, on at least one major surface of the substrate, lands and grooves as a rewrite region in which data is rewritten, the distance between the outer perimeter of the rewrite region and the center of the spiral or circle of the grooves is 58.5 mm or less, and the distance between the centers of a land and a groove adjacent to each other is 0.61 .mu.m to 0.62 .mu.m.

Inventors: Yoshida; Nobuhisa (Zushi, JP), Suzuki; Katsumi (Chofu, JP)

Assignee: Kabushiki Kaisha Toshiba

International Classification: G11B 7/007 (20060101); G11B 7/00 (20060101); G11B 7/26 (20060101); G11B 7/24 (20060101); G11B 7/006 (20060101); G11B 007/24 ()

Expiration Date: 12/26/2017